/opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/lib/ffwd/plugin/json/connection.rb:71:in `rescue in receive_json': undefined method `error' for nil:NilClass (NoMethodError)
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/lib/ffwd/plugin/json/connection.rb:50:in `receive_json'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/lib/ffwd/plugin/json.rb:71:in `receive_data'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/eventmachine-1.0.3/lib/eventmachine.rb:187:in `run_machine'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/eventmachine-1.0.3/lib/eventmachine.rb:187:in `run'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/lib/ffwd/core.rb:128:in `run'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/lib/ffwd.rb:360:in `main'
from /opt/rbenv/ffwd-all/versions/2.1.0/lib/ruby/gems/2.1.0/gems/ffwd-0.2.2/bin/ffwd:9:in `<top (required)>'
from /opt/rbenv/ffwd-all/versions/2.1.0/bin/ffwd:23:in `load'
from /opt/rbenv/ffwd-all/versions/2.1.0/bin/ffwd:23:in `<main>'